Broadcasting television signals by satellite is a common method of providing television service. Typically, communication satellites positioned in earth-synchronous orbits provide television signals to various countries around the world. Efforts have been made to standardize the national television standards of these countries in order facilitate television service. Frequently, however, the national television standards of these countries differ from country to country.
One such standard includes the audio standard for direct reception from satellites for multichannel sound. In order to provide television service to countries with varying audio standards, it is desirable to equip a television receiver so as to provide a multistandard audio receiving capability. In this regard, reference is made to an article entitled "Digitaler Multistandard Audio-Chipsatz", published in Elektronik on Mar. 16, 1990. In addition, reference is also made to "AMU 2481 VS Audio Processor for Video Recorders and Satellite Receivers", published in Intermetall on Feb. 18, 1991.
Generally, present satellite transmission systems for television utilize frequency modulation (FM). A disadvantage with these systems is that the individual FM sound carriers are distributed over numerous different positions within the intermediate sound frequencies. Consequently, in order to facilitate tuning to a specific multisound channel, the user is required to have knowledge of the respective positions of the FM sound carriers. In addition, these systems require that the television receiver is capable of accurately adjusting to the desired heterodyne frequency.
Therefore, it is an object of the present invention to provide search tuning for sound carriers that does not require knowledge of the position of the sound carrier within an intermediate sound frequency range.